Op Monday 11 October 2004 12:40, schreef Miguel: > Rene wrote: > >> I looked at the same Gaussian 03 output with v9 and v10. > >> With V9 I could see the geometry optimization results AND the > >> vibrational results at the end. I completely lost that with the 10 > >> version... > > I don't know what the 'geometry optimization' is. Please explain
Quantum Mechanics (QM) software (e.g. Gaussian, Mopac and many more) can do a search for the most stable (i.e. with lowest energy) compound... often, for such searched the start structure, all intermediate and end structures are given... I think people look at this to see how effective the search was... Anyway, this animation does show you a bit where the energy barriers are in the structure/energy 'landscape'... This langscape is the polydimensional space where the energy is plotted versus some coordinate... the simplest is the 'time' in the search, but Rene also mentioned that he would be very interested in seeing such a plot for internal coordinates, e.g. a bond length in the structure... An example. Say we have the structure H-H, but the starting structure is not 'optimal', i.e. the bond length is slightly longer than the equilibrium bond length, and hence, the QM energy is not minimal... the geometry optimization would then, e.g. using steepest decent, search in coordinate space for more energy stable structures... which would mean, the search would go towards the equilibrium distance... > >> I was hoping to use the Gaussian03 reader as a starting point to do the > >> NWChem reader, but it looks like a lot of functionality that I liked > >> has been lost.... > > If v9 better meets your needs then you should keep using it. But if you start coding... it would be better to code on v10, because Miguel and I stopped active development of v9, which is the last released version of the 'b6' branch in CVS... (So, to get the source of v9, so a cvs checkout like cvs -r b6 -d Jmol-b6 co Jmol, or so... see CVS help). This allowed us to fully focus on v10. > The main focus of the v10 release was to make a replacement for Chime. > There was some collateral damage in the process, in large part because I > don't understand a lot of the energy/vibration stuff. > > Other than the UI control panels, I doubt if any of the *lost* > functionality is more than a few days' worth of work. Very likely... e.g. going to frame 10 of the vibrations would be the script command 'frame 10'... it only needs to get linked to some GUI element... (Though a fully script-based GUI, would require a script command to retrieve the number of vibrations... is that available?) > > The Gaussian03 reader should be able to read the vibrations, and thought > > it did the energy optimization too... Miguel? > > Don't know ... what is this? If the Gaussian file has something like "# bla/bla opt" on the first line (or second?), it means a geometry optimization... such files will have more than one geometries in the file, and the current v10 reader might very well just take the first (starting structure), or last (the optimized structure)... The gaussian reader of v9, read all structures as frames, so that people could browse through the structures created during the search for the most energy stable geometry... Egon ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ Jmol-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jmol-users
